IBM’s Selectric line of typewriters were quite popular in the 1960s, thanks in part to an innovation called the typeball which allowed for easy font changes on a single machine. Unfortunately, as if often the case when specialized components are involved, it’s an idea that hasn’t aged particularly well. The Selectric typewriters are now around 60 years old and since IBM isn’t making replacement parts, those restoring these machines have had to get somewhat creative like using a 3D printer to build new typeballs.